Zenith 17Y20 is in Sam's Photofact #335-19. Sam's can usually be ordered through local libraries. Sam's also sells information by calling 800-428-7267.
Here are some older TV schematics. Your TV isn't listed but there may be a similar model.
http://www.earlytelevision.org/tv_schematic_diagrams.html
Norm:
Does anyone know where i could download a schamatic for my tv its is a zenitih 17y20
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